RingBack Tone Service is a kind of service that allows a user to customize a ringback tone. When a calling user terminal dials a called user terminal, a piece of dulcet music or compliment, or a prompt speech recorded and synthesized by the called user, instead of a normal ringback tone, will be played to the calling user terminal after the called user terminal alerts and before the called user answers. Due to the characteristic of individualization, the ringback tone service has become a fad and is warmly welcomed. However, although there are various solutions to realize the ringback tone service, such as an exchange solution, an intelligent network solution, a called user customization solution and a calling user customization solution, etc, the usual ringback tones are all pre-customized; and at most, different ringback tones are played according to different user numbers, sessions and sites, etc, but different ringback tones cannot be sent according to the current state of the calling user, and the requirements of the user cannot be met more flexibly.
Presence Service is a kind of service in which presence information of a user (presentity), such as state, mood and communication capability, may be obtained in real time and presented to other users (watcher), so that it is convenient for the watcher to select a suitable communication mode or time to communicate with the presentity. But at present, there are some problems in the application of the presence service in the field of telecom. For example, many called users use old terminals, or the presence client ends are not turned on for various reasons, thus the presence information cannot be obtained to popularize the presence service in this field, as a result, users are baffled from having a better communication experience via the presence service.
In conclusion, the existing ringback tone service and the presence service are inconvenient and deficient in practical application, and neither of them can meet the strict requirements of users on the communication service. Therefore, the ringback tone service and the presence service need to be improved.